Spring structure



c. s. REED SPRING STRUCTURE Filed sept. 25, 1953 y INVENTOR Y C/a/'r 5.Reed /vmx` ATTORNEY v Patented May 12, 1936 sri" PATENT OFFICEv oldsSpring Company, Jackson, poration of Delaware Mich., a cor- ApplicationSeptember 25, 1933, Serial No. 690,795

1 Claim.

The present invention relates to improvements in spring structure `andhas particular reference in seat constructions for vehicles.

In the design of seat constructions to be used in vehicles, it isnecessary to provide for extraordinary use and eXtreme ridingconditions. At the present time this is accomplished by a marginal upperframe which is usually of wire and is supported in position by amarginal row of coil springs and braced in some suitable manner. Thefront of the marginal frame and front marginal springs are relied uponprimarily to impart the proper contour and shape to the seat constuctionand to provide a resilient support for the thighs of the occupant; thecentral part of the seat construction supporting the bulk of theoccupants weight and being subjected to the maximum deflection andcompression. The practice has been to so interconnect the centralsprings with the marginal frame and springs that excessive compressionof the central spring tends to draw the marginal frame and springinwardly. Repeated inward deflection of the front of the marginal framehas a tendency to permanently distort the same with the result that thesame sags inwardly destroying the contour of the entire spring structureand trim and materially affects the riding qualities. Also, this inwarddistortion of the marginal frame often results in the diagonal bracesbeing loosened and projected forwardly through the trim. Furthermore, inconstructions of the type just described, the helices of the centralcoil springs can be considered as suspended as a unit from the marginalframe and springs with the result that upon compression the centralsprings do not have an opportunity to function in an unrestrained mannerbut are stiffened to a degree and renderedV less yieldable to localizedpressure. This last mentioned characteristic impairs the maximum feeland possible riding quality of the construction.

Thus it becomes the primary object of this invention to provide a springconstruction of the general type disclosed in the Costigan ReissuePatent No. 18,860 and the Burch Patent No. 1,793,421 in which thecentral area of coil springs is positioned and aligned by the marginalsprings and frame yet is capable of action substantially free fromrestraint due to differential compression or deflection between thecentral area and marginal area of the seat construction; permanentdistortion and excessive inward deflection of the marginal frame beingalso avoided.

Other objects and advantages reside in the hereinafter describedcombinations and arrangements of parts. The invention is clearly denedin the appended claim.

In the drawing,

Fig. 1 is a plan View of one-half a spring structure embodying thepresent invention.

Fig. 2 is a transverse sectional view taken upon line 2-2 of Fig. 1. Y Y

In general the present invention resides in a spring structure in whichthe marginal frame and coil springs maybe of usual construction. Withinthemarginal area is provided a central area of spring coils which mayVlikewise be of usual construction and association. Between the marginaland central area resilient means are provided, preferably in the formofclose wound helical springs, for yieldably suspending and positioningthe central area from the marginal frame in a manner permittingexcessive differential compression or deflection between the respectiveareas without objectionable inward distortion of the marginal frame.With the present invention specically applied to the Burch and Costigantype of constructions heretofore mentioned, a pair of parallel verticallistingl strips are provided inthe space vbetween the adjacent rows ofcoil springs dening the inner border of the marginal spring area and theouter border of the central spring area. The edges of the strips arereinforced with a flexible member and are secured to the adjacent tophelices of the springs. Close wound helical springs are connected atopposite ends to the top helices of' adjacent springs and extend betweenthe pairs of parallel listing strips. These strips together with thoselocated between adjacent rows of springs in the central area function toretain the springs under compression Vand to assist in the lateralsupport and alignment of the springs. By having pairs of listing stripsin spaced opposed relation between the marginal and central areas, theproper contour and compression of the adjacent springs in the two areasmay be readily maintained; the listing strips I8 act as a marginal framework for the central area preventing uncontrolled relative shifting ofthe two areas. As the spacing of the adjacent rows of springs isgreatest at the junction between the marginal and central areas, theaddition of the listing strips I9 located at this point acts to supportthe upholstering and avoid the formation of pockets in which the paddingmay accumulate.

That the invention may be clearly understood, specific reference is madeto the drawing wherein a spring construction particularly designed forthe seat cushion oi a vehicle is illustrated as comprising an uppermarginal or border wire frame I to which the top helices of a marginalrow of coil springs Il are clipped or secured in any suitable manner.The springs may be of any one of the several known types and may havetheir base helices secured to a marginal base frame I2 in a manner wellknown in the manufacture of spring structures.

The coil springs I 3, which constitute the central area, have theiradjacent top helices secured together by suitable means such as wireclips I4. These clips may also have the additional function of securingthe top helices of adjacent rows of springs to the reinforced edges ofthe listing strips l5 which are employed as in the patents to Burch andCostigan heretofore mentioned to retain the springs under initialcompression and to render the construction quiet in operation. The upperedges of the listing strips I5 are shown as reinforced by close woundhelicals I 6 although any suitable flexible member may be employed forthis purpose. The lower edges of the listing strips I5-I8-I 9 arepreferably reinforced in some suitable manner as disclosed in the abovementioned patents and suitably clipped or secured to the bottom coils ofthe spring I3 as shown in Fig. 2. The springs I3 may be lighter and thussofter than the springs I I but this it not essential and I do not careto limit myself to any particular selection of springs in the marginaland central areas. Usual diagonal braces are designated as I'I; it beingunderstood that any other suitable lateral bracing may be employed.

Paralleling the front and rear sides of the marginal frame I0 andlocated between the marginal and central spring areas, are spacedparallel listing strips I8--I9. These strips may be identical with thestrips I5 and may be clip-ped to the top helices of the springs I I-I3in the same manner as heretofore described. The spacing between thesprings II and the marginal springs I3 of the central area, and likewisethe, spacing between the listing strips I8-|9, is such as to permit theinsertion of longitudinally extensible members such as close woundhelical springs 20. These springs function to position and align thesprings of the central areas from the marginal frame l!) yet at the sametime permit differential compression of the marginal and central areasthrough longitudinal extension without objectionable drawing in anddistortion of the marginal frame I0. The helicals 20 also permit thecentral area of springs I3 to function substantially independently ofthe marginal area with the result that the riding action is improved andthe central springs are more sensitive to localized pressure imparting asofter feel to the construction.

- Although only a single row of springs Il is shown in what is termedthe marginal area, obviously, two or more rows may be employed withinthe scope of the invention if it is desired to locate the central areaof springs further inwardly.

The single embodiment of the invention represents one practical andeffective manner of carrying out the present invention. Othermodifications and changes are contemplated but it is thought that theforegoing disclosure is sufcient to enable those skilled in the art toresort to such modifications and changes without departing from thescope of the invention as defined in the claim.

What I claim as new and desire to protect by Letters Patent is:

In a spring construction for vehicle seats, the combination of an upperborder frame of wire having front, end and rear sides, of front and rearmarginal rows of spaced coil springs having the top helices thereofclipped along said front and rear sides, inner rows of coil springssubstantially paralleling said front marginal rows and being similarlyspaced and in substantially aligned relation with respect to the springsof said front marginal rows, adjacent rows of said inner rows beingclosely disposed with springs in adjacent rows thereof in opposedrelation and the top helices thereof clipped together, the most adjacentof said inner rows to said front marginal row being spaced asubstantially greater distance from said front marginal row than thespacing of adjacent inner rows, a flexible vertically disposed striplocated between adjacent rows of said inner rows, a spaced pair offlexible vertically disposed strips located between said front marginalrow and said inner row most adjacent thereto, said strips between saidadjacent inner rows being secured at the upper edges to the top helicesof the springs and to the lower part of the spring structure at theirlower edges to hold the springs under compression, said spaced pair ofstrips being similarly secured to the inner side of said front marginalrow and to the outer side of said inner row most adjacent thereto,horizontally disposed helical springs connecting the top helices ofaligned spaced springs in said front marginal row and said inner rowmost adjacent thereto, said spaced pair of strips bridging the spacingbetween the springs in rows with which they are associated and acting torender support to the upholstery padding in the region of maximumspacing between the springs and to control the contour of said marginalrow and said inner rows most adjacent thereto, said horizontallydisposed helical springs constituting the only direct connection betweenthe upper part of said inner rows of springs and Said front marginal rowof springs whereby permanent distortion of said front side of said upperframe following excessive differential depression of said front marginalrow and said inner rows of springs is obviated.

CLAIR S. REED.

